1. Field of the Invention
The present invention relates to a process for managing air speed with a view to complying with the time constraints of an aerodyne in an unsettled meteorological environment.
2. Discussion of the Background
In general, it is known that the current trend is for the flight management systems of aerodynes to be ever more intimately incorporated into the air traffic management mechanisms, by involving digital ground/on-board communication means, more accurate locating means and more powerful computing means on the ground. Furthermore, these aerodynes carry on-board equipment which makes it possible to take into account ever more reliable and accurate meteorological forecasts. It therefore becomes possible to improve compliance with time constraints and therefore to reduce the admissible time windows associated with these constraints.
Furthermore, the strategy for the time constraints is different for each of the partners of the air transport.
Customarily, the pilot desires to manage these constraints as flexibly as possible (perhaps avoiding them) while taking into account the inaccuracy in the weather forecasts. In fact, he wants to avoid large variations in aircraft speed and engine revs for reasons of aircraft performance and engine lifetime.
For his part, the air traffic controller desires that the time constraints be managed as far upstream as possible of the flights so as to benefit from extra distance in order to cope with the time constraint by reducing (or increasing) the aircraft speed whilst leaving the aircraft on its path. In fact, the air traffic controller prefers to give instructions regarding time of transit as early as possible during the cruising segment. Thus, the traffic flows as forecast without creating additional conflicts.
It turns out that in spite of the abovementioned means, possible causes of error remain, especially in the realm of meteorological forecasts, which may lead to non-compliance with the time constraints.